
namespace Terra.Core.Common.Utils;

/// <summary>
/// 日期时间工具类
/// </summary>
public static class DateTimeUtils
{
    #region 时间戳操作

    /// <summary>
    /// 获取当前时间戳（毫秒）
    /// </summary>
    public static long GetTimestamp() => DateTime.Now.ToTimestamp();

    /// <summary>
    /// 将时间戳转换为DateTime
    /// </summary>
    public static DateTime FromTimestamp(long timestamp) => timestamp.FromTimestamp();

    #endregion

    #region 友好显示

    /// <summary>
    /// 转换为友好时间显示
    /// </summary>
    public static string ToFriendlyDisplay(DateTime dateTime) => dateTime.ToFriendlyDisplay();

    #endregion

    #region 时间范围

    /// <summary>
    /// 获取指定时间范围
    /// </summary>
    public static (DateTime Start, DateTime End) GetDateRange(DateRangeType rangeType)
    {
        var now = DateTime.Now;
        return rangeType switch
        {
            DateRangeType.Today => (now.Date, now.Date.AddDays(1).AddSeconds(-1)),
            DateRangeType.Yesterday => (now.Date.AddDays(-1), now.Date.AddSeconds(-1)),
            DateRangeType.ThisWeek => (now.GetMonday(), now.GetSunday()),
            DateRangeType.LastWeek => (now.AddDays(-7).GetMonday(), now.AddDays(-7).GetSunday()),
            DateRangeType.ThisMonth => (now.GetFirstDayOfMonth(), now.GetLastDayOfMonth()),
            DateRangeType.LastMonth => (now.AddMonths(-1).GetFirstDayOfMonth(), now.AddMonths(-1).GetLastDayOfMonth()),
            _ => throw new ArgumentException("无效的时间范围类型", nameof(rangeType))
        };
    }

    #endregion

    #region 项目特定扩展

    /// <summary>
    /// 获取工作日天数（排除周末）
    /// </summary>
    public static int GetWorkDays(DateTime startDate, DateTime endDate)
    {
        var days = 0;
        for (var date = startDate.Date; date <= endDate.Date; date = date.AddDays(1))
        {
            if (date.IsWeekday())
            {
                days++;
            }
        }
        return days;
    }

    /// <summary>
    /// 检查是否在工作时间（默认9:00-18:00）
    /// </summary>
    public static bool IsWorkingHour(DateTime? dateTime = null, TimeSpan? startTime = null, TimeSpan? endTime = null)
    {
        var time = (dateTime ?? DateTime.Now).TimeOfDay;
        var start = startTime ?? new TimeSpan(9, 0, 0);
        var end = endTime ?? new TimeSpan(18, 0, 0);
        return time >= start && time <= end;
    }

    #endregion

    /// <summary>
    /// 获取开始时间
    /// </summary>
    /// <param name="dateTime"></param>
    /// <param name="days"></param>
    /// <returns></returns>
    public static DateTime GetBeginTime(DateTime? dateTime, int days = 0)
    {
        if (dateTime == DateTime.MinValue || dateTime == null)
            return DateTime.Now.AddDays(days);

        return dateTime ?? DateTime.Now;
    }

    /// <summary>
    ///  时间戳转本地时间-时间戳精确到秒
    /// </summary>
    public static DateTime ToLocalTimeDateBySeconds(long unix)
    {
        return DateTimeOffset.FromUnixTimeSeconds(unix).ToLocalTime().DateTime;
    }

    /// <summary>
    ///  时间转时间戳Unix-时间戳精确到秒
    /// </summary>
    public static long ToUnixTimestampBySeconds(DateTime dt)
    {
        return new DateTimeOffset(dt).ToUnixTimeSeconds();
    }

    /// <summary>
    ///  时间戳转本地时间-时间戳精确到毫秒
    /// </summary>
    public static DateTime ToLocalTimeDateByMilliseconds(long unix)
    {
        return DateTimeOffset.FromUnixTimeMilliseconds(unix).ToLocalTime().DateTime;
    }

    /// <summary>
    ///  时间转时间戳Unix-时间戳精确到毫秒
    /// </summary>
    public static long ToUnixTimestampByMilliseconds(DateTime dt)
    {
        return new DateTimeOffset(dt).ToUnixTimeMilliseconds();
    }

    /// <summary>
    /// 毫秒转天时分秒
    /// </summary>
    /// <param name="ms"></param>
    /// <returns></returns>
    public static string FormatTime(long ms)
    {
        int ss = 1000;
        int mi = ss * 60;
        int hh = mi * 60;
        int dd = hh * 24;

        long day = ms / dd;
        long hour = (ms - day * dd) / hh;
        long minute = (ms - day * dd - hour * hh) / mi;
        long second = (ms - day * dd - hour * hh - minute * mi) / ss;
        long milliSecond = ms - day * dd - hour * hh - minute * mi - second * ss;

        string sDay = day < 10 ? "0" + day : "" + day; //天
        string sHour = hour < 10 ? "0" + hour : "" + hour;//小时
        string sMinute = minute < 10 ? "0" + minute : "" + minute;//分钟
        string sSecond = second < 10 ? "0" + second : "" + second;//秒
        string sMilliSecond = milliSecond < 10 ? "0" + milliSecond : "" + milliSecond;//毫秒
        sMilliSecond = milliSecond < 100 ? "0" + sMilliSecond : "" + sMilliSecond;

        return string.Format("{0} 天 {1} 小时 {2} 分 {3} 秒", sDay, sHour, sMinute, sSecond);
    }

    /// <summary>
    /// 获取unix时间戳
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static long GetUnixTimeStamp(DateTime dt)
    {
        return ((DateTimeOffset)dt).ToUnixTimeMilliseconds();
    }

    /// <summary>
    /// 获取日期天的最小时间
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static DateTime GetDayMinDate(DateTime dt)
    {
        return new DateTime(dt.Year, dt.Month, dt.Day, 0, 0, 0);
    }

    /// <summary>
    /// 获取日期天的最大时间
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>

    public static DateTime GetDayMaxDate(DateTime dt)
    {
        return new DateTime(dt.Year, dt.Month, dt.Day, 23, 59, 59);
    }

    /// <summary>
    /// 获取日期天的最大时间
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static string FormatDateTime(DateTime? dt)
    {
        if (dt == null) return string.Empty;

        if (dt.Value.Year == DateTime.Now.Year)
            return dt.Value.ToString("MM-dd HH:mm");
        else
            return dt.Value.ToString("yyyy-MM-dd HH:mm");
    }

    /// <summary>
    /// 获取今天日期范围00:00:00 - 23:59:59
    /// </summary>
    /// <returns></returns>
    public static List<DateTime> GetTodayTimeList(DateTime time)
    {
        return new List<DateTime>
        {
            Convert.ToDateTime(time.ToString("D").ToString()),
            Convert.ToDateTime(time.AddDays(1).ToString("D").ToString()).AddSeconds(-1)
        };
    }

    /// <summary>
    /// 获取星期几
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static string GetWeekByDate(DateTime dt)
    {
        var day = new[] { "星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六" };
        return day[Convert.ToInt32(dt.DayOfWeek.ToString("d"))];
    }

    /// <summary>
    /// 获取这个月的第几周
    /// </summary>
    /// <param name="daytime"></param>
    /// <returns></returns>
    public static int GetWeekNumInMonth(DateTime daytime)
    {
        int dayInMonth = daytime.Day;
        // 本月第一天
        DateTime firstDay = daytime.AddDays(1 - daytime.Day);
        // 本月第一天是周几
        int weekday = (int)firstDay.DayOfWeek == 0 ? 7 : (int)firstDay.DayOfWeek;
        // 本月第一周有几天
        int firstWeekEndDay = 7 - (weekday - 1);
        // 当前日期和第一周之差
        int diffday = dayInMonth - firstWeekEndDay;
        diffday = diffday > 0 ? diffday : 1;
        // 当前是第几周，若整除7就减一天
        return ((diffday % 7) == 0 ? (diffday / 7 - 1) : (diffday / 7)) + 1 + (dayInMonth > firstWeekEndDay ? 1 : 0);
    }
}

/// <summary>
/// 时间范围类型
/// </summary>
public enum DateRangeType
{
    /// <summary>
    /// 今天
    /// </summary>
    Today,

    /// <summary>
    /// 昨天
    /// </summary>
    Yesterday,

    /// <summary>
    /// 本周
    /// </summary>
    ThisWeek,

    /// <summary>
    /// 上周
    /// </summary>
    LastWeek,

    /// <summary>
    /// 本月
    /// </summary>
    ThisMonth,

    /// <summary>
    /// 上月
    /// </summary>
    LastMonth
}